See horseshoe crabs mate tonight and at full moon in June

Tonight is the big night this month to see horseshoe crabs pile up on each other to mate. The biggest spawns will be on beaches in New Jersey and Delaware, but you may be able to see them from Massachusetts to Florida. They like the full moon high tide, which is at about 11:30 in NJ tonight, though check your local tide charts.

The giant, harmless crabs mate throughout May and June, piling up on beaches several deep. Females are bigger; males just pile on. The crabs numbers are in decline, largely because conch fishermen use them as bait. Plus, they are breakfast for endangered loggerhead sea turtles and migrating birds, particularly the red knot, Calidris canutus. And climate change may be pushing their numbers down, too, a study last year by USGS says.

Horseshoe crabs mating

The best times to see them are high and low tides on new and full moon. But if you show up a few days on either side of those events, you still have a good chance. I had thought it was a lot of hype, but when I was surprised how many there were when I went to see them in Delaware one night. Hundreds were piled up on the beach.

The best way to see them is to volunteer to be part of the survey. You have to go to horseshoe crab counting school first.

According to the Horseshoe Crab Census, the biggest nights are tonight and June 15.

horseshoecrab Where to SEE HORSESHOE CRABS




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